I am having a very common problem among owners of Gen II Runners who tow boats, etc. Even the slightest of tounge weight, or even a bunch of cargo in cargo area will cause my Runner to sag about an inch. It looks like a lot more, but it is only an inch of sag with my boat trailer attached(when measuring from top of tire tread to bottom of fender well. Recently, I replaced the rear shocks and springs with inexpensive aftermarket parts from Advanced Auto Parts. Initially this made the rear end sit up much higher. I didn't measure, but on a flat surface, the rear end was as high if not a tiny bit higher than the front end. It was great to drive...for a few months. I have finally "broke in the new coil springs, and it is like it was before, with exception to the fact that it rides much better than with the 15 yr old worn out shocks. I want to lift the rear end up a bit and was thinking of either purchasing a 2 inch rear end lift (Leveling) kit from ebay for about $80, or buying shocks that have an air hose comming from them that you can inflate at the gas station to level your rear end when you are towing. I cannot find these on ebay and I don't know what they are called. They were at the auto parts store a few years ago. Does anyone have any advice? i really don't want to spend an arm and a leg, but I know that you get what you pay for.

 

I replaced my springs and it fixed all of your above problems. and they ride good all the time, no adjusting nothing. loaded or unloaded they ride very well. I used the All Pro 1.5" coil (Have been discontinued) and they work great. the downey spring or the OME spring would be good too, a bit more money though.

you could do an air spring...

http://www.airliftcompany.com/al1000.html

 

You can do it either way. The correct way would probably be to replace the springs. I put air shocks on my truck & they work great. Picked them up at autozone. Autozone will say that they don't have them but they do! Go to the Gabriel shock website & search for the air shocks for your truck, then take the part number & search it on the autozone website. I paid $65 bucks for the pair with all the hoses & everything else.

 

The best way is to spend some money and stop buying el cheapo parts. I had Downey coils with Bilstein shocks in mine. It never sagged in the 4 years I ran them.

 

I put Air shocks on her yesterday. I bought the set from Autozone for $75 and installed them in less than an hour. It states that you have a minimum psi of 20 and max of 200. I have them set at 140. This gives me a good amount of lift and doesn't allow the rear end to sag much with the boat hooked up. It rides pretty well now A bit rougher than before, but what the hell, it's a truck not a caddie, right?